All of the men were Iraqis and had been convicted of terror charges, the official said, speaking on condition of anonymity.

The latest executions brought to 50 the number of times Baghdad has carried out the death penalty so far this year, despite widespread calls for a moratorium on the country's use of capital punishment.

Iraq's executions have sparked concern from the United Nations, as well as from Britain, the European Union and human rights groups Amnesty International and Human Rights Watch.

Justice Minister Hassan al-Shammari insisted last month that Baghdad would continue to implement the death penalty, disregarding widespread calls for it to issue a moratorium.

In June, Amnesty International called on authorities to "refrain from using the death penalty, commute the sentences of all those on death row, believed to number several hundred, and declare a moratorium on executions."

The rights group has condemned the “alarming” increase in execution by the Iraqi government in 2012 as the numbers had doubled from the previous year.

In August of last year Iraq executed 21 people – three of them women – in a single day of similar terror charges.